Taxonomy

Comments (0)

Transcript of Taxonomy

Taxonomythe branch of biologyconcerned with namingand classifying organismsEarly TaxonomyAristotle384 BC-322 BCAristotle classified all lifeas either plant or animal.(A 2-Kingdom system)He also usedcommon names...His animal kingdom subcategories:Air animalsLand animalsWater animalsProblems here???Aristotle called a certainanimal a "kounabi"Mr Caudill's Dad called it a "polecat"So what is it???Other problems with common names?Jellyfish?Dogwood?Bark!What's wrong withthis system?????Carolus Linnaeus(1707--1778)The Father of ModernTaxonomyLinnaues developed thesystem of binomialnomenclature--everyorganism is given ascientific name consistingof 2 words (a binomial)first word: Genussecond word: speciesin Latin!Why Latin??Latin is a "dead" language.No one speaks it so it doesnot evolve into dialects....and Latin was theofficial scientificlanguage of the day...Rules for writingbinomials:1. The Genus is alwayscapitalized.2. The species is alwayslower-cased.3. Both words areitalicized orunderlined.(Mr. Caudill wants you to underline them!)Rana pipiens = leopard frogMusa acuminata = bananaHomo sapiens = You...get the idea.......How do we classify organisms?Classification of Life:a hierarchical system is usedwhere organisms are grouped into7 categories (taxa) of decreasingsize:Phylum/Division*ClassOrderFamilyGenusspecies(*Use Phylum for Animals andDivision for Plants.)These are the 7main taxa:You can also insert additional taxaby adding sub- and super- asprefixes. Ex: subphylum, superorderExample: Classification of HumansKingdom: AnimaliaPhylum: ChordataSubphylum: VertebrataSuperclass: TetrapodaClass: MammaliaOrder: PrimatesFamily: HominidaeGenus: Homospecies: sapiensHow do we categorizeorganisms into taxa?We base it on.....Phylogeny--an organism'sevolutionary history--orhow closely it's related toother organismsHow are phylogenies determined?in the 21st century, we use....Comparative Biochemistry--seuqencing DNA or the amino acids in proteins to look for similaritiesKingdomHierarchical System:Which two animals are most closely related?REVIEW:What makes a group of organisms the same species?if they canreproduceand havefertile offspringAnother Taxon: the DOMAINThe DOMAIN is larger than the KINGDOM